If you drink coffee without knowing that you are pregnant, it means that you just drank coffee when you were pregnant. If the amount of coffee consumed is relatively small, it will not have much effect on the embryonic tissues and there is no need to worry too much. The main component of coffee is caffeine, which has an excitatory effect on the nervous system and can easily affect the fetus through the placenta, but in the early stages of pregnancy, the embryonic tissues are not yet fully developed and the organs are not yet formed, so there will not be much effect. External factors such as viruses, chemical substances and rays can easily affect the development of the fetus during the formation of the fetal organs, such as causing malformations in fetal development. It is recommended that you do not need to deal with it for the time being, but you can follow the doctor’s advice to have regular maternity checkups, especially between 22-26 weeks of pregnancy, you need to go to the hospital for Down screening test and 4D ultrasound to confirm whether the fetus has abnormal development, and terminate the pregnancy in time if abnormalities are found.